BILLBUILDS
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making alkyl halides
i was reading my chem textbook today and i stumbled across a way to make some usefull chemicals - if it works
can i go to a local welder and get him to dissolve some acetylene in methylene chloride and then add elemental bromine to make methylene bromide? or
the same with iodide
bromomethane is useful in forming methylene bridges between two hydroxy groups on a benzene ring much faster than methylene chloride
CH2=CH2 + Br2 --- CCl2H2---> CH2Br2
you could also do the classic test for an alkene and expose it to UV light but i dont know how you would contain this reaction or the products
1,2-OH-C6H5 + CH2Br2 -> benzodioxole
extend this to other useful alkylhalides
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Texium
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Thread Moved
4-2-2017 at 09:03 |
A Halogenated Substance
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If you're going to do the alkene + halogen method, you're very likely going to need an ice bath for temperature control. I remember reading an account
of someone's experience of adding bromine to an alkene and they reported that the reaction fired the test tube across the room (that's all the
information I remember; if I refind the story, I'll post a link with a quote).
You could alternatively make alkyl halides by taking an alcohol (secondary or tertiary is usually better) and place it in reflux with a hydrohalic
acid with a metal-halide salt catalyst with the anion corresponding to the particular halogen you're attempting to add to the alcohol.
ROH + HX ---MX, reflux---> RX + H2O
Where:
X=halogen
M=Metal
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Amos
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Why not perform the Finklestein reaction on dichloromethane to get the even more reactive diiodomethane?
Or better yet, just use dichloromethane itself. I'm pretty sure it's safrole you're after given the nature of your posts so far on this forum, and I
think you cook-types generally manage just fine with DCM.
[Edited on 2-8-2017 by Amos]
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JJay
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Acetylene is an alkyne and would first produce a mixture of cis- and trans- 1,2-dibromoethene by electrophylic addition, after which further
halogenation would lead to 1,1,2,2-tetrabromoethane, which I believe is fairly resistant to oxidation.
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